The caregiver (for example, parents or nursing personnel) will put a person to be nursed (for example, a child or an elderly person) in a seat when busy to prevent an accident from occurring on the person to be nursed. For the convenience of observing the person to be nursed and for the sake of enhancing the sense of security of the person to be nursed, the front face of the person to be nursed is usually face the caregiver. However, the caregiver have to consume a lot of energy to observe and move the person to be nursed, and it is difficult for the person to be nursed to see the caregiver without interruptions, so the use experience of the caregiver and the person to be nursed can be affected, and the safety of the seat can be also reduced.